Signaling system



June 12, 1928.

S. P. SHACKLETON S IGNALING SYSTEM Filed March 15, 1927 Service Ta 6 z sfight Inwmd IN V EN TOR.

azislmmm ATTORNEY Patented June 12, 1928.

UNITED STATES 1 1,672,957 PATENT OFFICE.

SAMUEL P. BHACKLETON, OF WYOMING, NEW YORK, ASSIGNOR T0 AMERICAN TELE-PHONE AND TELEGRAPH COMPANY, A CORPORATION OF NEW YORK.

SIGN ALING SYSTEM.

Application filed March 15, 1927. Serial No. 175,582.

This invention relates to telephone trans mission circuits, and moreparticularly to signaling arrangements associated therewith.

In telephone practice, difliculty is experienced due to poor insulationof conductors, and particularly of conductors contained in centralotfice cabling. This causes faulty op eration of lamps or other signalsat telephoneswitchboards. This dilhculty is more pronounced undercertain atmospheric conditions, and undesired grounded circuits whichmaintain the lamps or signals in false operated condition occur as aresult of such leakage.

It is one of the objects of this invention to provide a simple andefficient si naling circuit which will obviate this diflicu ty.

Another object consists in providing a discharge tube in connection withthe signalingcircuits, such, for example, as a neon tube or other tubehaving similar character istics, which will cooperate with said cir''cuits.

Other and further objects will appear more fully from the followingdetailed de scription, when considered in connection with theaccompanying drawing, in which one embodiment of the invention isillustrated.

In the drawing, a telephone transmission or toll line is indicated asterminating at different ositions in a telephone switchboard. T e tollline which is shown for the purpose of illustration, has its conductorsrepresented by the character 5. O The trans mission line 5 has aplurality of jacks, as shown by the designations 6, 7, 8 and 9,multipled thereto. bignaling lamps 10, 11, 12 and 13 are associated,respectively, with each of the jacks 6, 7, 8 and 9 for each position.The lighting of lamps 10, 11, and 13 indicate an incoming coil, and thekey 14 may be employed in connection with the group of lamps to transfercalls from one position to the other by extinguishing a lamp in oneposition and lighting a lamp at another position. A group of busysignals is associated with each position, as indicated at 15, 16,17 and18. These signals may be used'inconnection with the jacks 6, 7 8 and 9,respectively. The signals are represented as being discharge tubes, suchas a neon or other tube which will present high resistance under normalconditions, but when a poten* tial is impressed across the tubesufiicient to break down its high resistance, the How of current isestablished through the tube which maintains a comparatively lowresistance therein. A. relay 19 is operated in response to an incomingcall over the toll conductors 5 under control relays energized by thetransmission of ringing current over the said conductors, as willpresently appear. The relay 19 maintains the signals 15, 16, 17 and 18in operated conditionduring the call. (jontactsprings 20 and 21 areassociated with the armature olrelay 19 and serve to momentarilyestablish ground potential on the battery side of the tubes toetl'ectively short-circuit them and reestablish the normal high internalresistance of the tubes upon the de-energization of relay 19 at thetermination of a call.

In the operation of the improved system, the transmission of ringingcurrent over the line conductors 5 causes the operation of ringing relay22which is bridgedacross said conductors through leads 23 and backcontact of relay 24. The energization of relay 22 closes a circuit fromits grounded contact, conductor 25, winding of relay 26, conductor 27 tobattery through the right contact of relay 24. The closure of thiscircuit causes the energization of relay 26, which completes a circuitthrough its make contact from ground, right-hand winding of relay 28 tobattery, thus operating the latter relay. The energization of relay 28closes a locking circuit from ground through its left-hand Winding andmake contact over conductor 27, contact of relay 24 to battery. Acircuit is also closed at this time from battery, closed contact ofrelay 24, conductor 27, left make contact of relay 28, transfer key 14,conductors 29 and 29, filaments of lamps 10, 11 and 13 to ground,thereby causing the illumination of said lamps. The energization ofrelay 28 also closes a circuit through its right make contact frombattery, conductor 30, winding of relay 19 to ground. This circuitcauses the operation of relay 19, which completes a circuit from groundthrough its front make contact, over conductors 31 and 32 and throughsignals 15, 16, 17 and 18 in parallel to battery, causing each of thesesignals to operate and indicate a busy condition.

In response to the lighting of lamps 10 and 11, the operator will inserta plug with the customary cord circuit in jack 6. Buttery is connectedto the sleeve of this plug, and a circuit is completed over the sleeveof jack 6, conductor 33, Winding-of relay 24 to ground. The closureoifthis circuit causes the operation of relay 24 which closes its contactsand opens the circuit by which ringing relay 22 is energized, and alsothe circuit over which lamps 1O, '11 and 13 are lighted. The opening 01'these circuits causes the de-energization ot' 'relay22 and theextinctionof lamps 10, 11, and 13. The operation of relay 24; also causes thedeenergi'zation ol' relays 26 and 28; Relay 19 which was energized by acircuit controlled by these relays, is now maintained operated by relay24,1) a circuit from battery, front contact of re ay ll, conductor 30,winding of relay 19' to ground.

The incoming call will be completed at the position Where jack 6 islocated, when possible, or transferred by means oi" key l i to someother position where it can be completed in a well understood manner.

"At the completion of the call, the cord circuit is dissociated from thejack in'which it is plugged and the circuitby which relay 24 wasenergized willbe broken, this relay releasing. The release of relay 24causes the release of relay 19of the signaling circuit. Relay 19,upon'releasing, closes a short-cir cuit from ground through its armatureand upper make contact, spring '20, spring '21, conductor 32' tobattery. This circuit is only momentarily established, but sufficienttime is allowedto lace ground potential on the battery sideo the tubesto effectively, shortc'ircuit them and reestablish the normal highinternal resistance of the tubes. The normal high resistance.characteristics, of the tubes are thus re-established, and the falseandcontinued operation of the tubes by a grounded circuit caused byleaka e through adjacent conductors is eliminate lVhile there is shownand described herein a certain preferred form of the invention by wayotillustration, it will be understood that it is not limited or confinedto the grecise details of construction herein descr1 ed and delineated,as modification'and Variation may be made within the scope of the claimswithout departing from the spirit of the invention.

What is claimed is: '1. A signaling circuit including a plural ity ofdischarge tubes connected therewith, a relay associated with thesignaling circuit operable to establish a current path over one sidethereof to cause the simultaneous operation of said tubes, andmeansresponsive to the release of said relay for short-circuiting saidtubes over the other side of said circuit.

2. A signaling circuit including a plurality'ot discharge tubesconnected therewith, relay means for closing said signaling cirsaidtubesassociated cuit to operate said for cuit, and means controlled by therelease of I the relay means for momentarilyiuiming said short circuit.i

3. A signaling circuit including a plural-' ity of-neon tubes connectedtherewith, a relay associated with the signaling circuit operable overone side thereof to cause the simultaneous I o eration of said tubes,and means responsive to the release of said rela for short-circuitingsaid tubes over the other side of said circuit.

4.. A signaling circuit having a plurality ofdischar'getubes connectedtherewith, said discharge tubes tern of 'hi resistance, a relayassociated wit the s sling-circuit operable to impress suficient otentnlon one side thereof to operate t e discharge tubes, and means res onsiveto the release of said relay for short circ'uitin'gsaid' dis: chargetubes over the other side of the signaling circuit to reestablish theirTe s'istance.

5. A signaling system com rising a rality' of pairs of conductors evil;9. le covering, a series of discharge til es connected in parallel toeach pairof conductors, a relay associatedwith eachpair of conductorsand operable to establish scumrg yath over one side thereof to cause theSim meous operation of said-dischargwubes, and means responsive to therelease of Said relay for short-circuiting said discharge tubes over theotherside of said circuittol'turn them to normal condition nidiprevemtheir continued operation b a ounded circuit rovided by leakage tlirouadjacent 601iuctors in the ca 1e;

6. A signaling system comprising a pinrality of pairs of conductorsavijpgla Gable covering, a series of discharge ues connected in parallelto each pair of conductors, said discharge tubesbeing normall'y ofhighresistance, a relay associated with eaehpa r of conductors and operableto iIIi fesss'dfficient potential over one side ereof to cause thesimultaneous operation o' fsai'dfdischarge tubes, by breaking down thehigh remally high resistance connected in parallelto each pair ofoonduotors'relay mea s as sociated with each palr'of conductors To!closing a circuit thereover to operate its as sociated tubes, a shortcircuit for said tubes associated with each pair of conductors and meanscontrolled by the relay means for momentarily closing the short circuitto permit the return of the discharge tubes to normal condition andprevent their false operation by any grounded circuit which may beprovlded by leakage through adjacent conductors in the cable.

In testimony whereof, I have signed my name to this specification this14th day of March 1927.

SAMUEL P. SHACKLETON.

